46 lines
1.4 KiB
ReStructuredText
46 lines
1.4 KiB
ReStructuredText
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.. _advanced:
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========
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Advanced
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========
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*EMQ* 2.0-rc.2 release supports `Local Subscription` and `Shared Subscription`.
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------------------
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Local Subscription
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------------------
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The *EMQ* broker will not create global routes for `Local Subscription`, and only dispatch MQTT messages on local node.
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.. code-block:: shell
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mosquitto_sub -t '$local/topic'
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mosquitto_pub -t 'topic'
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Usage: subscribe a topic with `$local/` prefix.
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-------------------
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Shared Subscription
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-------------------
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Shared Subscription supports Load balancing to distribute MQTT messages between multiple subscribers in the same group::
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---------
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| | --Msg1--> Subscriber1
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Publisher--Msg1,Msg2,Msg3-->| EMQ | --Msg2--> Subscriber2
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| | --Msg3--> Subscriber3
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---------
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Two ways to create a shared subscription:
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+-----------------+-------------------------------------------+
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| Prefix | Examples |
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+-----------------+-------------------------------------------+
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| $queue/ | mosquitto_sub -t '$queue/topic |
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+-----------------+-------------------------------------------+
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| $share/<group>/ | mosquitto_sub -t '$share/group/topic |
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+-----------------+-------------------------------------------+
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